1. Field of the Invention
This invention relates to sewing machines, and more specifically to improved means to be incorporated in a sewing machine to adapt the latter for stitching slide fastener stringers to the edges of padded ski pants and other relatively thick articles bounding openings therein.
2. Description of the Prior Art
Great difficulties have been encountered in machine sewing fastener stringers onto, for example, the folded slit-bounding edges at the bottoms of ski pants padded with polyurethane foam or like spongy material. The resiliency of the padding is such that the edges of such articles cannot possibly be held neatly folded and placed in position over the stringer tapes as they are fed under the presser foot of a sewing machine. It has therefore been practically impossible to stitch fastener stringers directly onto the folded edges of such padded articles.
In an attempt to overcome this problem, it has been suggested to baste or stitch, before final stitching, a pair of separated fastener stringers onto the right sides of the article edges, with the elements carrying edges of the stringer tapes disposed away from each other. Then, with the rows of elements interengaged by a slider movable therealong, only the article edges are folded back along the basting lines, wrong sides together, and the fastener stringers are finally stitched so as to form the so-called lap seams.
This scheme, however, provides only a partial solution to the above noted problem when employed in conjunction with a conventional sewing machine. The edges of padded ski pants or the like, even if basted to the fastener stringers, are easy to unfold immediately before being drawn under the presser foot of the sewing machine by its feed mechanism, so that it is highly difficult to form the desired lap seams in the case of such thick and resilient articles.